Package structure having redistribution layer structures

ABSTRACT

A package structure and a method of manufacturing the same are provided. The package structure includes a die, a RDL structure, an encapsulant and a conductive terminal. The die is on a redistribution layer (RDL) structure. The RDL structure comprises a polymer layer and a RDL in the polymer layer. The encapsulant is on the RDL structure and laterally aside the die. The encapsulant comprises a body part and an extending part underlying the body part. The conductive terminal is electrically connected to the RDL structure and the die. The body part of the encapsulant encapsulates sidewalls of the die. The extending part of the encapsulant extends into the polymer layer.

BACKGROUND

The semiconductor industry has experienced rapid growth due tocontinuous improvements in the integration density of various electroniccomponents (i.e., transistors, diodes, resistors, capacitors, etc.). Forthe most part, this improvement in integration density has come fromcontinuous reductions in minimum feature size, which allows more of thesmaller components to be integrated into a given area. These smallerelectronic components also require smaller packages that utilize lessarea than previous packages. Some smaller types of packages forsemiconductor components include quad flat packages (QFPs), pin gridarray (PGA) packages, ball grid array (BGA) packages, and so on.

Currently, integrated fan-out packages are becoming increasingly popularfor their compactness.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1A to FIG. 1H are schematic cross-sectional views illustrating amethod of forming a package structure according to some embodiments ofthe disclosure.

FIG. 2A to FIG. 2E are schematic cross-sectional views of packagestructures according to some embodiments of the disclosure.

FIG. 3A to FIG. 3C are schematic cross-sectional views of packagestructures according to some embodiments of the disclosure.

FIG. 4A to FIG. 4E are top views of package structures according to someembodiments of the disclosure.

DETAILED DESCRIPTION

The following disclosure provides many different embodiments, orexamples, for implementing different features of the provided subjectmatter. Specific examples of components and arrangements are describedbelow to simplify the present disclosure. These are, of course, merelyexamples and are not intended to be limiting. For example, the formationof a second feature over or on a first feature in the description thatfollows may include embodiments in which the second and first featuresare formed in direct contact, and may also include embodiments in whichadditional features may be formed between the second and first features,such that the second and first features may not be in direct contact. Inaddition, the present disclosure may repeat reference numerals and/orletters in the various examples. This repetition is for the purpose ofsimplicity and clarity and does not in itself dictate a relationshipbetween the various embodiments and/or configurations discussed.

Further, spatially relative terms, such as “beneath”, “below”, “lower”,“on”, “above”, “upper” and the like, may be used herein for ease ofdescription to describe one element or feature's relationship to anotherelement(s) or feature(s) as illustrated in the FIG.s. The spatiallyrelative terms are intended to encompass different orientations of thedevice in use or operation in addition to the orientation depicted inthe FIG.s. The apparatus may be otherwise oriented (rotated 90 degreesor at other orientations) and the spatially relative descriptors usedherein may likewise be interpreted accordingly.

Other features and processes may also be included. For example, testingstructures may be included to aid in the verification testing of the 3Dpackaging or 3DIC devices. The testing structures may include, forexample, test pads formed in a redistribution layer or on a substratethat allows the testing of the 3D packaging or 3DIC, the use of probesand/or probe cards, and the like. The verification testing may beperformed on intermediate structures as well as the final structure.Additionally, the structures and methods disclosed herein may be used inconjunction with testing methodologies that incorporate intermediateverification of known good dies to increase the yield and decreasecosts.

FIG. 1A to FIG. 1H are schematic cross-sectional views illustrating amethod of forming a package structure according to a first embodiment ofthe disclosure.

Referring to FIG. 1A, a carrier 10 is provided. The carrier 10 may be aglass carrier, a ceramic carrier, or the like. A release layer 11 isformed on the carrier 10 by, for example, a spin coating method. In someembodiments, the release layer 11 may be formed of a polymer-basedmaterial such as an Ultra-Violet (UV) glue, a Light-to-Heat Conversion(LTHC) material, an epoxy-based thermal-release material, or the like.The release layer 11 is decomposable under the heat of light to therebyrelease the carrier 10 from the overlying structures that will be formedin subsequent steps.

A first polymer layer 12 is formed on the release layer 11. The firstpolymer layer 12 may be a single layer structure or a multi-layerstructure. In some embodiments, the first polymer layer 12 includespolybenzoxazole (PBO), polyimide (PI), benzocyclobutene (BCB), ajinomotobuildup film (ABF), solder resist film (SR), or the like, or acombination thereof, but the disclosure is not limited thereto. In someother embodiments, the first polymer layer 12 may be replaced by adielectric layer. The dielectric layer may include a nitride such assilicon nitride, an oxide such as silicon oxide, an oxynitride such assilicon oxynitride, phosphosilicate glass (PSG), borosilicate glass(BSG), boron-doped phosphosilicate glass (BPSG), or the like, or acombination thereof. The first polymer layer 12 is formed by a suitablefabrication technique such as spin-coating, lamination, deposition, orthe like. The deposition includes chemical vapor deposition, forexample.

Still referring to FIG. 1A, a redistribution layer (RDL) 13 is formed onthe first polymer layer 12. The RDL 13 includes conductive materials.The conductive materials includes metal, metal compound or metal alloy,such as copper, nickel, titanium, aluminum, copper alloy, aluminumalloy, titanium nitride or the like, or a combination thereof. In someembodiments, the RDL 13 includes a seed layer (not shown) and aconductive layer formed thereon (not shown). The seed layer may be ametal seed layer such as a copper seed layer. In some embodiments, theseed layer includes a first metal layer such as a titanium layer and asecond metal layer such as a copper layer over the first metal layer.The conductive layer may be copper or other suitable metals.

In some embodiments, the RDL 13 is formed by the following processes: aseed layer is formed on the first polymer layer 12 by sputtering, forexample. A patterned mask is formed on the seed layer, the patternedmask have a plurality of openings exposing a portion of the top surfaceof the seed layer. The conductive layer is formed on the seed layerexposed by the openings of the patterned mask through plating, forexample. Thereafter, the patterned mask is stripped, the seed layer notcovered by the conductive layer is removed by an etching process. Thus,the conductive layer and the underlying seed layer form the RDL 13.

Referring to FIG. 1B, a second polymer layer 14 is formed on the firstpolymer layer 12 and the RDL 13, so as to cover the top surface of thefirst polymer layer 12, the top surface and the sidewalls of the RDL 13.In some embodiments, the second polymer layer 14 includespolybenzoxazole (PBO), polyimide (PI), benzocyclobutene (BCB), ajinomotobuildup gilm (ABF), solder resist film (SR), or the like, or acombination thereof, but the disclosure is not limited thereto. In someother embodiments, the second polymer layer 14 may be replaced by adielectric layer. The dielectric layer may include a nitride such assilicon nitride, an oxide such as silicon oxide, an oxynitride such assilicon oxynitride, phosphosilicate glass (PSG), borosilicate glass(BSG), boron-doped phosphosilicate glass (BPSG), or the like, or acombination thereof. The second polymer layer 14 is formed by a suitablefabrication technique such as spin-coating, lamination, deposition, orthe like. The material and the forming method of the second polymerlayer 14 may be the same as or different from those of the first polymerlayer 12.

Referring to FIG. 1B and FIG. 1C, the second polymer layer 14 ispatterned or partially removed to form a plurality of via holes 15 andat least one recess 16 in the second polymer layer 14. The removalmethod includes, for example, exposure and development processes, laserdrilling process, photolithography and etching processes, or acombination thereof. The via holes 15 and the recess 16 may be formedsimultaneously or successively. The via holes 15 expose a portion of thetop surface of the RDL 13. The recess 16 may expose a portion of the topsurface of the RDL 13, but the disclosure is not limited thereto. Insome other embodiments, the recess 16 may not expose the RDL 13. Inother words, the sidewalls of the recess 16 exposes the second polymerlayer 14, and the bottom of the recess 16 may expose the second polymerlayer 14 or/and the RDL 13. In some embodiments, the depth H1 of therecess 16 may less than, equal to, or larger than the depth H2 of thevia hole 15. In some embodiments, the depth H2 may also be referred asthe depth of the RDL 13, that is, the distance from the top surface ofthe second polymer layer 14 to the top surface of the RDL 13.

The cross section shapes of the via hole 15 and the recess 16 may besquare, rectangle, inverted trapezoid, or other suitable shapes,respectively. The sidewalls of the via hole 15 and the recess 16 may bestraight or inclined, respectively. The cross section shapes and sizesof the via hole 15 and the recess 16 may be the same or different.

In some embodiments, the first polymer layer 12, the RDL 13 and thesecond polymer layer 14 having the via holes 15 and the recess 16 form aRDL structure 18. The RDL structure 18 includes a die attaching region18 a and a periphery region 18 b surrounding the die attaching region 18a.

In some embodiments, the recess 16 is closer to the die attaching region18 a than the via holes 15. In some embodiments, the via holes 15 isformed in the periphery region 18 b, the recess 16 may be formed in theperiphery region 18 b, the die attaching region 18 a, or a combinationthereof. In some embodiments, the recess 16 may be a trench, a hole, ora combination thereof.

Referring to FIG. 1D and FIG. 1E, a patterned mask layer (such aspatterned photoresist) 19 having a plurality of openings 19 a is formedon the RDL structure 18. The patterned mask layer 19 may be a patternedphotoresist. The patterned mask layer 19 covers a portion of the topsurface of the second polymer layer 14 and fills into the recess 16. Inother words, the die attaching region 18 a, the recess 16, and a portionof the periphery region 18 b of the RDL structure 18 is covered by thepatterned mask layer 19. The opening 19 a is located over and overlappedwith the via hole 15, exposing a portion of the top surface of thesecond polymer layer 14, the sidewalls of the second polymer layer 14and the top surface of the RDL 13 exposed in the via hole 15.

Thereafter, a plurality of through integrated fan-out vias (TIVs) 20 areformed on the RDL 13 and the second polymer layer 14 exposed by theopening 19 a. The TIV 20 includes metal, metal alloy, metal compound, ora combination thereof. The patterned mask layer 19 is then stripped. TheTIV 20 is electrically connected to the RDL 13.

In some embodiments, the TIV 20 includes a seed layer and a conductivelayer formed on the seed layer. The seed layer is, for example, atitanium or/and copper composited layer, and is formed by a sputteringor a suitable technique. The seed layer is formed on the RDL structure18 before the patterned mask layer 19 is formed. The conductive layer(e.g., a copper layer) is formed on the seed layer exposed by theopenings 19 a by plating, for example. Thereafter, the patterned masklayer 19 is stripped, the seed layer not covered by the conductive layeris removed. The conductive layer and the underlying seed layer form theTIV 20. In some embodiments, the sidewalls of the TIV 20 may be straightor inclined. The number of the TIVs 20 formed on RDL structure 18 shownin FIG. 1D is merely for illustration, and the disclosure is not limitedthereto.

Referring to FIG. 1E, a die 28 is attached to the die attaching region18 a of the RDL structure 18. In some embodiments, the die 28 is one ofa plurality of dies cut apart from a wafer, for example. The die 28 maybe an application-specific integrated circuit (ASIC) chip, an analogchip, a sensor chip, a wireless and radio frequency chip, a voltageregulator chip or a memory chips. The number of the die 28 shown in FIG.1E is merely for illustration, and the disclosure is not limitedthereto. In some embodiments, two or more dies 28 may be mounted on theRDL structure 18, and the two or more dies 28 may be the same types ofdies or the different types of dies.

Still referring to FIG. 1E, the die 28 is disposed between the TIVs 20,that is, the TIVs 20 are laterally aside or around the die 28. In someembodiments, the die 28 includes a substrate 22, a plurality of pads 23,a passivation layer 24, a plurality of connectors 25 and a passivationlayer 26. The pads 23 may be a part of an interconnection structure (notshown) and electrically connected to the integrated circuit devices (notshown) formed on the substrate 22. The passivation layer 24 is formedover the substrate 22 and covers a portion of the pads 23. A portion ofthe pads 23 is exposed by the passivation layer 24 and serves as anexternal connection of the die 28. The connectors 25 are formed on andelectrically connected to the pads 23 not covered by the passivationlayer 24. The connector 25 includes solder bumps, gold bumps, copperbumps, copper posts, copper pillars, or the like. The passivation layer26 is formed over the passivation layer 24 and aside the connectors 25to cover the sidewalls of the connectors 25. The passivation layers 17and 19 respectively include an insulating material such as siliconoxide, silicon nitride, polymer, or a combination thereof. The materialsof the passivation layer 24 and the passivation layer 26 may be the sameor different. In some embodiments, the top surface of the passivationlayer 26 is substantially level with the top surface of the connectors25.

In some embodiments, the die 28 is attached to the second polymer layer14 of the RDL structure 18 through an adhesive layer 21 such as a dieattach film (DAF), silver paste, or the like. The adhesive layer 21 isformed on the back side of the die 28. Herein, the back side refers to aside opposing the frond side (the side close to the connectors 25, thatis, close to an active surface of the die 28) of the die 28. In someembodiments, attaching the die 28 to the RDL structure 18 includes thefollowing processes: forming an adhesive material layer on the back sideof the die 28, the adhesive layer 21 may include a flowable material.The die 28 with the adhesive material layer is bonded to the secondpolymer layer 14 of the RDL structure 18. Thereafter, a curing processis performed, such that the adhesive material layer is cross-linked andcured to form the adhesive layer 21.

In some embodiments, the width W2 of the adhesive layer 21 is equal tothe width W1 of the die 28, and the sidewall of the adhesive layer 21may be aligned with the sidewall of the die 28, but the disclosure isnot limited thereto. In some other embodiments, the width W2 of theadhesive layer 21 may be larger than the width W1 of the die 28, and thesidewall of the adhesive layer 21 is not aligned with the sidewall ofthe die 28.

Referring to FIG. 1F, an encapsulant 30 is then formed on the RDLstructure 18 to encapsulate the sidewalls of the die 28 and the TIVs 20.In some embodiments, the encapsulant 30 includes a molding compound, amolding underfill, a resin such as epoxy, a combination thereof, or thelike. In some other embodiments, the encapsulant 30 includes aphoto-sensitive material such as polybenzoxazole (PBO), polyimide,benzocyclobutene (BCB), a combination thereof, or the like, which may beeasily patterned by exposure and development processes or laser drillingprocess. In alternative embodiments, the encapsulant 30 includes nitridesuch as silicon nitride, oxide such as silicon oxide, phosphosilicateglass (PSG), borosilicate glass (BSG), boron-doped phosphosilicate glass(BPSG), a combination thereof, or the like. The encapsulant 30 may beformed by the following process: forming an encapsulant material layeron the RDL structure 18, the die 28 and the TIVs 20 by a suitablefabrication technique such as spin-coating, lamination, deposition, orsimilar processes. The encapsulant material layer encapsulates the topsurfaces and sidewalls of the die 28 and the TIVs 20. Thereafter, aplanarization process such as a grinding or polishing process isperformed to remove a portion of the encapsulant material layer, suchthat the top surfaces of the connectors 25 of the die 28 and the TIVs 20are exposed. In some embodiments, the top surfaces of the die 28, theTIVs 20 and the encapsulant 30 are substantially coplanar with eachother.

Referring to FIG. 1F, the encapsulant 30 covers the top surface of theRDL structure 18, the sidewalls of the die 28, the sidewalls of theadhesive layer 21 and the sidewalls of the TIVs 20. In some embodiments,the encapsulant 30 fills into the recess 16 of the second polymer layer14 of the RDL structure 18. The encapsulant 30 covers and contacts withthe inner surface of the recess 16. In some embodiments in which therecess 16 exposes the sidewall and the bottom surface of the secondpolymer layer 14 and a portion of the top surface of the RDL 13, theencapsulant 30 covers and contacts sidewalls of the second polymer layer14 and the top surface of the RDL 13 exposed in the recess 16. In otherwords, the encapsulant 30 is engaged with the RDL structure 18, and aportion of the encapsulant 30 contacting with the second polymer layer14 has a step profile.

In other words, the encapsulant 30 includes a body part 30 a and anextending part 30 b. The body part 30 a is located on the top surface TPof the second polymer layer 14 of the RDL structure 18, encapsulatingsidewalls of the die 28 and sidewalls of the TIV 20. The extending part30 b is located underlying the body part 30 a and extends to be embeddedin the second polymer layer 14.

In some embodiments, the extending part 30 b is located on the RDL 13and the second polymer layer 14 and laterally aside the second polymerlayer 14, covering and contacting the sidewalls and bottom surface ofthe second polymer layer 14 or/and the top surface of the RDL 13 exposedby the recess 16. The extending part 30 b is overlapped with a portionof the second polymer layer 14 in the direction parallel with the topsurface TP of the RDL structure 18 or the top surface of the die 28. Thebottom surface of the extending part 30 b is lower than the bottomsurface of the die 28, the bottom surface of the adhesive layer 21 andthe top surface TP of the second polymer layer 14 of the RDL structure18. In some embodiments in which the depth H1 (FIG. 1C) of the recess 16is equal to the depth H2 (FIG. 1C) of the RDL 13, the bottom surface ofthe extending part 30 b may be in contact with and coplanar with the topsurface of the RDL 13, but the disclosure is not limited thereto. Insome other embodiments in which the depth H1 of the recess 16 is lessthan the depth H2 of the RDL 13, the bottom surface of the extendingpart 30 b may be higher than the top surface of the RDL 13 (not shown).

As the encapsulant 30 includes an extending part 30 b extends to beembedded in the second polymer layer 14, the contact area between theencapsulant 30 and the second polymer layer 14 is increased. In someembodiments, the bottom surface of the body part 30 a, the bottomsurface and sidewalls of the extending part 30 b are in contact withsecond polymer layer 14. That is to say, the contact area between theencapsulant 30 and the second polymer layer 14 is larger than the bottomsurface of encapsulant 30 (extending in a direction parallel with thetop surface of the die 28 or the top surface of the RDL structure 18).The cross section shape of the extending part 30 b may be square,rectangle, inverted trapezoid, or the like. The height H3 of theextending part 30 b may be less than or equal to the depth H2 of the RDL13. However, the disclosure is not limited thereto, the extending part30 b may have any shape or height, as long as it extends into the secondpolymer layer 14 or/and the first polymer layer 12 and the contact areabetween the encapsulant 30 and the second/first polymer layer(s) 14/12is increased.

Referring to FIG. 1G, a redistribution layer (RDL) structure 32 isformed over and electrically connected to the die 28 and the TIVs 20.The RDL structure 32 is referred to as a “front-side redistributionlayer structure” through the specification, wherein the “front-side”refers to a side close to the connectors 25 of the die 28. In someembodiments, the RDL structure 32 includes a plurality of third polymerlayers PM1, PM2, PM3 and PM4 and a plurality of redistribution layersRDL1, RDL2, RDL3 and RDL4 stacked alternately. The number of the polymerlayers or the redistribution layers shown in FIG. 1G is merely forillustration, and the disclosure is not limited thereto.

The third polymer layer PM1 is located on and in contact with the topsurface of the die 28, the top surface of the encapsulant 30 and aportion of the top surface of the TIV 20. In some embodiment, theencapsulant 30 is not extending into the second polymer layer 14, thecontact area between the third polymer layer PM1 and the encapsulant 30is less than the contact area between the second polymer layer 14 andthe encapsulant 30.

The redistribution layer RDL1 penetrates through the third polymer layerPM1 and is electrically connected to the connectors 25 of the die 28 andthe TIVs 20. The redistribution layer RDL2 penetrates through the thirdpolymer layer PM2 and is electrically connected to the redistributionlayer RDL1. The redistribution layer RDL3 penetrates through the thirdpolymer layer PM3 and is electrically connected to the redistributionlayer RDL2. The redistribution layer RDL4 penetrates through the thirdpolymer layer PM4 and is electrically connected to the redistributionlayer RDL3.

In some embodiments, each of the third polymer layers PM1, PM2, PM3 andPM4 includes a photo-sensitive material such as polybenzoxazole (PBO),polyimide (PI), benzocyclobutene (BCB), a combination thereof or thelike. In some embodiments, each of the redistribution layers RDL1, RDL2,RDL3 and RDL4 includes conductive materials. The conductive materialsincludes metal such as copper, aluminum, nickel, titanium, alloysthereof, a combination thereof or the like, and is formed by anelectroplating process. In some embodiments, the redistribution layersRDL1, RDL2, RDL3 and RDL4 respectively includes a seed layer (not shown)and a metal layer formed thereon (not shown). The seed layer may be ametal seed layer such as a copper seed layer. In some embodiments, theseed layer includes a first metal layer such as a titanium layer and asecond metal layer such as a copper layer over the first metal layer.The metal layer may be copper or other suitable metals.

In some embodiments, the redistribution layers RDL1, RDL1, RDL3 and RDL4 respectively includes a plurality of vias V and a plurality of tracesT connected to each other. The vias V penetrate through the thirdpolymer layers PM1, PM2, PM3 and PM4 to connect the traces T of theredistribution layers RDL1, RDL1, RDL3 and RDL4, and the traces T arerespectively located on the third polymer layers PM1, PM2, PM3 and PM4,and are respectively extending on the top surface of the third polymerlayers PM1, PM2, PM3 and PM4.

In some embodiments, the topmost redistribution layer RDL4 is alsoreferred as under-ball metallurgy (UBM) layer for ball mounting.Thereafter, a plurality of connectors 33 are formed over andelectrically connected to the redistribution layer RDL4 of the RDLstructure 32. In some embodiments, the connectors 33 are made of aconductive material with low resistivity, such as Sn, Pb, Ag, Cu, Ni, Bior an alloy thereof, and are formed by a suitable process such asevaporation, plating, ball drop, or screen printing. In alternativeembodiments, the connectors 33 may be controlled collapse chipconnection (i.e. C4) bumps formed by a C4 process. In some embodiments,the connectors 33 are also referred as conductive terminals. Theconnectors 33 are electrically connected to the die 28 through the RDLstructure 32, and electrically connected to the RDL structure 18 throughthe RDL structure 32 and the TIVs 20.

Referring to FIG. 1G and FIG. 1H, thereafter, the release layer 11 isdecomposed under the heat of light, and the carrier 10 is then de-bondedfrom the overlying structure. And the package structure PKG1 is thuscompleted.

Referring to FIG. 1H, the package structure PKG1 includes the die 28,the encapsulant 30, the TIVs 20, the RDL structure 18, the RDL structure32 and the connectors 33. In some embodiments, the RDL structure 18 isformed at back side of the die 28, the RDL structure 32 is formed atfront side of the die 28. The encapsulant 30 is between the RDLstructure 18 and the RDL structure 32, laterally surrounding sidewallsof the die 28 and the TIVs 20. In some embodiments, the encapsulant 30comprises the extending part 30 embedded in the RDL structure 18. Theextending part 30 fills in the recess 16 of the second polymer layer 14.The height H3 of the extending part 30 b may be equal to the depth H2 ofthe RDL 13, and a portion of the top surface of the RDL 13 may beexposed in the bottom of the recess 16 and is in contact with theextending part 30. However, the disclosure is not limited thereto.

FIG. 2A to FIG. 2D are schematic cross-sectional views respectivelyillustrating a package structure according to some embodiments of thedisclosure. The package structures shown in FIGS. 2A to 2D are similarto the package structure PKG1 shown in FIG. 1H, except the extendingpart of the encapsulant or/and the adhesive layer may have differentstructural features which are described as below. For the sake ofbrevity, the similar features, materials and the forming methods are notdescribed again.

Referring to FIG. 2A, in some embodiments, in package structure PKG2,the recess 16 may not expose the RDL 13, and the extending part 30 b ofthe encapsulant 30 filled in the recess 16 is not in contact with theRDL 13. The depth of the recess 16 and the height H3 of the extendingpart 30 b may be less than, equal to, or larger than the depth H2 of theRDL 13. The bottom surface of the extending part 30 b may be higherthan, coplanar with or lower than the top surface of the RDL 13 or/andthe bottom surface of the TIV 20.

In some embodiments, the depth of the recess 16 is larger than thethickness of the second polymer layer 14, that is, the recess 16 isformed in the second polymer layer 14 and the first polymer layer 12.The bottom of the recess 16 exposes the first polymer layer 12, thesidewalls of the recess 16 exposes the second polymer layer 14 and thefirst polymer layer 12. The height H3 of the extending part 30 b islarger than the thickness of the second polymer layer 14, and the bottomsurface of the extending part 30 b is lower than the bottom surface ofthe RDL 13 and the top surface of the first polymer layer 12. That is,the extending part 30 b further extends to be embedded in the firstpolymer layer 12.

The bottom surface of the body part 30 a is in contact with the secondpolymer layer 14. The sidewalls of the extending part 30 b are incontact with the second polymer layer 14 and the first polymer layer 12.The bottom surface of the extending part 30 b is in contact with thefirst polymer layer 12. Therefore, the contact area between theencapsulant 30 and the second/first polymer layers 14/12 of the RDLstructure 18 is larger than the bottom surface of the encapsulant 30.

Referring to FIG. 2B, in some embodiments, in package structure PKG3,two recesses 16 a and 16 b are formed in the second polymer layer 14or/and the first polymer layer 12. In some embodiments, the two recesses16 a and 16 b are formed in the periphery region 18 b of the RDLstructure 18. Each of the recess 16 a and 16 b may have structuralfeatures similar to those of the recess 16 in foregoing embodiments. Therecess 16 a and the recess 16 b may have the same or different shapes orsizes. The encapsulant 30 fills into the two recesses 16 a and 16 b. Theencapsulant 30 includes two extending parts 30 c and 30 d underlying thebody part 30 a thereof. The extending part 30 c fills into the recess 16a, and the extending part 30 d fills into the recess 16 b. The extendingparts 30 c and 30 d are located in the periphery region 18 b of the RDLstructure 18. In some embodiments, the extending parts 30 c and 30 d arelocated between the TIVs 20 and the die 18. The extending parts 30 c and30 d may respectively similar to the extending part 30 b described inthe foregoing embodiments. The shapes, sizes and structural features ofthe extending parts 30 c and 30 d may be the same or different.

Referring to FIG. 2C, in some embodiments, in package structure PKG4,two recesses 16 a′ and 16 b may be formed in the RDL structure 18. Therecess 16 b is formed in the periphery region 18 b, and the recess 16 a′is formed in the periphery region 18 b and the die attaching region 18a. In other words, the recess 16 a′ is across the boundary between thedie attaching region 18 a and the periphery region 18 b. In someembodiments, the recesses 16 a′ and 16 b may be formed in the secondpolymer layer 14, respectively, but the disclosure is not limitedthereto. The recess 16 a′ and the recess 16 b may or may not expose theRDL 13 of the RDL structure 18, respectively. The shapes, sizes of therecesses 16 a′ and 16 b may be the same or different. Referring to FIG.1E and FIG. 2C, during the process of attaching the die 18 to the RDLstructure 18, the adhesive layer 21 fills into the recess 16 a′. In someembodiments, the recess 16 a′ is filled up with the adhesive layer 21.The recess 16 b is filled with the extending part 30 b of theencapsulant 30.

The adhesive layer 21 includes a body part 21 a and an embedded part 21b connected to each other. In some embodiments, the embedded part 21 bis under the ends of the body part 21 a. The encapsulant 30 includes abody part 30 a and an extending part 30 b under the body part 30 a. Insome embodiments, the bottom surfaces of the body part 21 a of theadhesive layer 21 and the body part 30 a of the encapsulant 30 aresubstantially coplanar with the top surface TP of the second polymerlayer 14. The bottom surface of the embedded part 21 b of the adhesivelayer 21 and the bottom surface of the extending part 30 b are lowerthan the top surface TP of the second polymer layer 14.

In some embodiments in which the recesses 16 a′ is formed in the secondpolymer layer 14, the bottom surface of the body part 21 a, the bottomsurface of the embedded part 21 b and the sidewalls of the embedded part21 b are in contact with the second polymer layer 14. That is to say,the contact area between the adhesive layer 21 and the second polymerlayer 14 of the RDL structure 18 is larger than the area of the bottomsurface of the adhesive layer 21 (extending in a direction parallel withthe top surface of the die 28 or the top surface of the RDL structure18). Further, the contact area between the adhesive layer 21 and thesecond polymer layer 14 of the RDL structure 18 is larger than thecontact area between the adhesive layer 21 and the die 28.

The embedded part 21 b may have similar structural feature to theextending part of the encapsulant 30 described above. The shapes, sizesof the embedded part 21 b of the adhesive layer 21 and the extendingpart 30 b of the encapsulant 30 may be the same or different. Theembedded part 21 b is located in the RDL structure 18, and laterallyaside the second polymer layer 14 or/and the first polymer layer 12. Insome embodiments, the embedded part 21 b is not in contact with the RDL13, but the disclosure is not limited thereto. In some other embodimentsin which the recess 16 a′ exposes the RDL 13, the embedded part 21 b maybe in contact with the RDL 13 (not shown). In some embodiments, thesidewall of the body part 21 a is align with the sidewall of the die 28,and the sidewall of the embedded part 21 b is not align with thesidewall of the die 18 or the sidewall of the body part 21 a. In someembodiments, the embedded part 21 b protrudes from the sidewalls of thedie 18 and the body part 21 a in a direction parallel with the topsurface of the die 18. However, the disclosure is not limited thereto.In some other embodiments, one sidewall of the embedded part 21 b may bealign with the sidewall of the die 28 and the sidewall of the body part21 a of the adhesive layer 21.

In some embodiments, a portion of the embedded part 21 b is covered bythe body part 21 a of the adhesive layer 21, and another portion of theembedded part 21 b is covered by the body part 30 a of the encapsulant30. In other words, a portion of the adhesive layer 21 overlaps aportion of the encapsulant 30 a in the direction perpendicular to thetop surface of the die 28 or the RDL structure 18.

In some embodiments, the top surface of the embedded part 21 b of theadhesive layer 21, the top surface of the extending part 30 b of theencapsulant are coplanar with the top surface of the second polymerlayer 14 of the RDL structure 18. The bottom surfaces of the embeddedpart 21 b and the extending part 30 b are lower than the bottom surfaceof the die 28, the bottom surface of the body part 21 a of the adhesivelayer 21 and the bottom surface of the body part 30 a of the encapsulant30. The bottom surface of the embedded part 21 b and the bottom surfaceof the extending part 30 b may be in the same level or different levels.The embedded part 21 b and the extending part 30 b may respectivelycontact or not contact with the RDL 13.

In some embodiments, the recess 16 a′ and the 16 b are spaced from eachother. The embedded part 21 b of the adhesive layer 21 and the extendingpart 30 b of the encapsulant 30 are spaced from each other by the secondpolymer layer 14 therebetween. That is, a portion of the second polymerlayer 14 is located between the embedded part 21 b of the adhesive layer21 and the extending part 30 b of the encapsulant 30. In other words,the embedded part 21 b of the adhesive layer 21, the extending part 30 bof the encapsulant 30, a portion of the second polymer layer 14 areoverlapped with each other in the direction parallel with the topsurface of the RDL structure 18 or the top surface of the die 28.

As illustrated is FIG. 2C, the depths of the recesses 16 a′ and 16 b areless than the thickness of the second polymer layer 14, and the recesses16 a′ and 16 b are formed in the second polymer layer 14, but thedisclosure is not limited thereto. In some other embodiments, the depthof the recesses 16 a′ and 16 b may be larger than the thickness of thesecond polymer layer 14, respectively, and the recesses 16 a′ and 16 bmay be formed in the second polymer layer 14 and the first polymer layer12, respectively. That is, the extending part 30 b of the encapsulant 30may extend into the second polymer layer 14 and the first polymer layer12.

Referring to FIG. 2D, in some embodiments, in package structure PKG5, arecess 16 c is formed in the die attaching region 18 a and the peripheryregion 18 b of the RDL structure 18. A portion of the recess 16 c isfilled with the adhesive layer 21, and another portion of the recess 16c is filled with encapsulant 30. In other words, the adhesive layer 21includes the body part 21 a and the embedded part 21 b. The encapsulant30 includes the body part 30 a and the extending part 30 b. Thestructural features of the embedded part 21 b and the extending part 30b are similar to those described in FIG. 2C, except the embedded part 21b and the extending part 30 b are located in the same recess 16 c. Inother words, the recess 16 c in which the embedded part 21 b is filledand the recess 16 c in which the extending part 30 b is filled are inspatial communication with each other.

In some embodiments, the embedded part 21 b fills a portion of therecess 16 c, and the encapsulant 30 fills another portion of the recess16 c not filled by the embedded part 21 b. The embedded part 21 b of theadhesive layer 21 and the extending part 30 b of the encapsulant 30 arein contact with each other and laterally aside each other. The bottomsurface of the embedded part 21 b and the bottom surface of theextending part 30 b are substantially coplanar with each other. Theinterface between the embedded part 21 b of the adhesive layer 21 andthe extending part 30 b of the encapsulant 30 may be not align with thesidewall of the die 28 or the sidewall of the body part 21 a of theadhesive layer 21, but the disclosure is not limited thereto. In someother embodiments, the interface between the embedded part 21 b of theadhesive layer 21 and the extending part 30 b of the encapsulant 30 maybe align with the sidewall of the die 28 or the sidewall of the bodypart 21 a of the adhesive layer 21. In some embodiments, the crosssection shapes of the embedded part 21 b and the extending part 30 b maybe square, rectangle, trapezoid, or inverted trapezoid or the like.

Referring to FIG. 2E, in some embodiments, in package structure PKG6, arecess 16 c′ is formed in the die attaching region 18 a and theperiphery region 18 b of the RDL structure 18. That is, the recess 16 c′is across the boundary of the die attaching region 18 a and theperiphery region 18 b. The recess 16 c′ is formed in the second polymerlayer 14 or/and the first polymer layer 12 of the RDL structure 18. Therecess 16 c′ is filled with the adhesive layer 21 and the encapsulant30. The adhesive layer 21 includes a body part 21 a and an embedded part21 b′. The encapsulant 30 includes a body part 30 a and an extendingpart 30 b. In some embodiments, the embedded part 21 b′ of the adhesivelayer 21 fills a portion of the recess 16 c′, and the cross sectionshape of the embedded part 21 b′ of the adhesive layer 21 may beL-shaped. The extending part 30 b of the encapsulant 30 fills anotherportion of the recess 16 c′ not filled by the embedded part 21 b′, thecross-section shape of the extending part 30 b may be square, rectangle,inverted L-shaped, or the like.

In some embodiments, the embedded part 21 b′ of the adhesive layer 21includes a vertical portion 21 c and a horizontal portion 21 d connectedto each other. The vertical portion 21 c of the embedded part 21 b′extends along a direction parallel with the sidewall of the die 28, andthe horizontal portion 21 d extends along a direction parallel with thetop surface of die 28. In some embodiments, at least a portion of thevertical portion 21 c is located in the die attaching region 18 a of theRDL structure 18. A first sidewall of the vertical portion 21 c contactsthe sidewall of the second polymer layer 14 or/and the first polymerlayer 12 exposed by the recess 16 c′ in the die attaching region 18 a.The second sidewall opposing the first sidewall of the vertical portion21 c may be aligned with the sidewall of the body part 21 c or thesidewall of the die 28, but the disclosure is not limited thereto. Insome other embodiments, the second sidewall of the vertical portion 21 cmay be not aligned with the sidewall of the body part 21 c or thesidewall of the die 28.

The horizontal portion 21 d of the embedded part 21 b′ is laterallyaside the vertical portion 21 c and covers a portion of the bottomsurface of the recess 16 c′. In some embodiments, the horizontal portion21 d extends to contact the sidewall of the second polymer layer 14or/and the first polymer layer 12 exposed by the recess 16 c′ inperiphery region 18 b, but the disclosure is not limited thereto. Insome other embodiments, the horizontal portion 21 d may not extend tocontact the sidewall of the second polymer layer 14 or/and the firstpolymer layer 12.

The extending part 30 b of the encapsulant 30 is located on thehorizontal portion 21 d of the embedded part 21 b′ of the adhesive layer21 and laterally aside the vertical portion 21 c of the embedded part 21b′ of the adhesive layer 21. In some embodiments in which the horizontalportion 21 d extend to contact the sidewall of the second polymer layer14 or/and the first polymer layer 12, the extending part 30 b contactsthe top surface of the horizontal portion 30 b, a portion of thesidewall of the vertical portion 21 c and a portion of the sidewall ofthe second polymer layer 14 or/and the first polymer layer 12. In someother embodiments in which the horizontal portion 21 d does not extendto contact the sidewall of the second polymer layer 14 or/and the firstpolymer layer 12, the extending part 30 b covers a portion of thesidewall of the vertical portion 21 c, the top surface and the sidewallof the horizontal portion 21 d and the sidewall of the second polymerlayer 14 or/and the first polymer layer 12.

It is noted that the shapes of the embedded part 21 b′ and the extendingpart 30 b shown FIG. 2D and FIG. 2E are merely for illustration, and thedisclosure is not limited thereto. The embedded part 21 b′ of theadhesive layer 21 and the extending part 30 b of the encapsulant 30 mayhave any shape, as long as the embedded part 21 b′ and the extendingpart 30 b fills in the recess 16 c′.

FIG. 3A to FIG. 3C illustrates examples of package structures includingdummy RDLs in the RDL structure.

Referring to FIG. 3A, in some embodiments, in package structure PKG7, aplurality of dummy RDLs 40 are included in the RDL structure 18. In someembodiments, the dummy RDLs 40 are formed at the same layer as the RDL13. Referring to FIG. 1A and FIG. 3A, the dummy RDLs 40 and the RDL 13are formed after the first polymer layer 12 is formed and before thesecond polymer layer 14 is formed. The materials and the forming methodof the dummy RDLs 40 and the RDL 13 may be the same or different. Thedummy RDLs 40 and the RDL 13 may be formed simultaneously orsuccessively. Herein, when elements are described as “dummy”, theelements are electrically floating or electrically isolated from otherelements. That is to say, the dummy RDLs 40 are electrically isolatedfrom the RDL 13.

Still referring to FIG. 3A, in some embodiments, the dummy RDLs 40 arelocated in the die attaching region 18 a and the periphery region 18 bof the RDL structure 18. In some embodiments, the dummy RDLs 40 arelocated on the first polymer layer 12, and may be configured as meshshaped, dot shaped or any other suitable shape, and the disclosure isnot limited thereto.

The recess 16 of the second polymer layer 14 may be located over thedummy RDL 40. In some embodiments, the recess 16 exposes the top surfaceof the dummy RDL 40 and a portion of the second polymer layer 14. Theencapsulant 30 fills into the recess 16, covering and contacting the topsurface of the dummy RDL 40 and the portion of the second polymer layer14 exposed by the recess 16. The other structural features of thepackage structure PKG7 are similar to those of the package structurePKG1 as described in FIG. 1H, and is not described again.

Referring to FIG. 3B, in some other embodiment, in package structurePKG8, the recess 16 does not expose the dummy RDLs 40. The recess 16 maybe formed in the second polymer layer 14 or/and the first polymer layer12. The encapsulant 30 fills into the recess 16 to cover and contact thesecond polymer layer 14 or/and the first polymer layer 12 exposed by therecess 16.

Referring to FIG. 3C, similar to the package structure PKG4, in apackage structure PKG 9, two recesses 16 a′ and 16 b are formed in theRDL structure 18. The recess 16 a′ is located in the die attachingregion 18 a and the periphery region 18 b. The recess 16 b is located inthe periphery region 18 b. The recess 16 a′ may or may not expose thetop surface of the dummy RDL 40. The recess 16 b may or may not exposethe top surface of the dummy RDL 40 or the top surface of the RDL 13. Insome embodiments, the encapsulant 30 fills into the recess 16 b, theadhesive layer 21 fills into the recess 16 a′. Except the RDL structure18 further includes dummy RDLs 40, the other structural features of thepackage structure PKG9 are similar to those of the package structurePKG4.

Similarly, in the package structures PKG1 to PKG6 (FIGS. 1H, and 2A to2E), the RDL structure 18 may also include dummy RDLs as shown in FIG.3A to FIG. 3C. In some other embodiments, the package structures PKG1 toPKG9 may not include dummy RDL, and some RDLs may be formed in the dieattaching region 18 a of the RDL structure 18. The some RDLs areelectrically connected to the RDLs 13, and are overlapped with the die28 in a direction perpendicular to the top surface TP of the RDLstructure 18.

FIG. 4A to FIG. 4E illustrates example of the shapes of the recessformed in the RDL structure in top view along the top surface of the RDLstructure according to some embodiments of the disclosure.

Referring to FIG. 1H, FIG. 2A, and FIG. 4A, in some embodiment, therecess 16 is formed in the periphery region 18 b of the RDL structure18. In some embodiments, the recess 16 is a continuous trench, therecess 16 may be a square ring shaped trench surrounding the dieattaching region 18 a, but the disclosure is not limited thereto. Insome other embodiments, the recess 16 may be rectangle ring shaped,round ring shaped or any other kind of ring shaped. The depth of therecess 16 may be adjusted according to product design. In someembodiments, the recess 16 is formed in the second polymer layer 14. Insome other embodiments, the recess 16 is formed in the second polymerlayer 14 and the first polymer layer 12.

The extending part 30 b of the encapsulant 30 is filled in the recess16, covering and contacting the sidewalls and bottom surface of thesecond/first polymer layer 14/12 of the RDL structure 18 exposed in therecess 16. In other words, the extending part 30 b of the encapsulant 30is located in a region enclosed by the sidewall of the second polymerlayer 14 or/and the first polymer layer 12. In some embodiments, theextending part 30 b in the recess 16 is located between the TIVs 20 andthe die attaching region 18 a.

Referring to FIG. 1H, FIG. 2A, and FIG. 4B, in some embodiments, therecess 16 includes a plurality of small recesses TR1 non-continuouslyconfigured in the second polymer layer 14 or/and the first polymer layer12. The recesses TR1 may be a trench or a hole, respectively. In someembodiments, the top view of the recess TR1 is rectangle, but thedisclosure is not limited thereto. In some other embodiments, the topview of the recess TR1 may be square, trapezoid, circle, oval, or anyother shape. The top view of different recesses TR1 may have the sameshape or different shapes. The extending part 30 b of the encapsulant 30fills into the recesses TR1 and thus has the same shape as the recessTR1.

Referring to FIG. 1H, FIG. 2A, and FIG. 4C, in some embodiments, therecess 16 includes a plurality of small recesses TR2 non-continuouslyconfigured in the second polymer layer 14 or/and the first polymer layer12. The top view of recess TR2 and the extending part 30 b may beL-shaped or inverted L-shaped.

Referring to FIG. 4D, the recess 16 may include a plurality of recessTR1 and TR2 with different shapes. For example, some recesses TR1 arerectangle. Some recesses TR2 are L-shaped or inverted L shaped.

Referring to FIG. 2B and FIG. 4E, two recesses 16 a and 16 b are formedin the periphery region 18 b of the RDL structure 18 are illustrated.The recess 16 a and the recess 16 b may have any shape as shown in FIG.4A to FIG. 4D.

It is noted that, the recess shown in the cross sectional views may haveany top view shown in FIGS. 4A to 4E, and the shapes of the recess ofthe polymer structure and encapsulant filled therein shown in thefigures are merely for illustration, the recess and the extending partof the encapsulant may have any shape, as long as a portion of theencapsulant is extend into the polymer(s) of the RDL structure and thecontact area between the encapsulant and the polymer layer of the RDLstructure is increased.

In the embodiments of the disclosure, as the encapsulant fills into therecess of the polymer layer of the RDL structure (that is, back side RDLstructure), the contact area between the encapsulant and the polymerlayer is increased. Therefore, the adhesion between the encapsulant andthe polymer layer is enhanced, and the encapsulant serves as a barrierto prevent water permeation, and the device reliability is thusincreased.

In accordance with some embodiments of the disclosure, a packagestructure includes a die, a RDL structure, an encapsulant and aconductive terminal. The die is on a redistribution layer (RDL)structure. The RDL structure comprises a polymer layer and a RDL in thepolymer layer. The encapsulant is on the RDL structure and laterallyaside the die. The encapsulant comprises a body part and an extendingpart underlying the body part. The conductive terminal is electricallyconnected to the RDL structure and the die. The body part of theencapsulant encapsulates sidewalls of the die. The extending part of theencapsulant extends into the polymer layer.

In accordance with alternative embodiments of the disclosure, a packagestructure includes a die, a first RDL structure, a TIV, an encapsulant,a second RDL structure and a conductive terminal. The die is on a firstpolymer layer of the first RDL structure. The TIV is located on andconnected to the first RDL structure, and laterally aside the die. Theencapsulant is on the first RDL structure, encapsulating sidewalls ofthe die and sidewalls of the TIV. The second RDL structure is on thedie, the TIV and the encapsulant. The conductive terminal iselectrically connected to the die through the second RDL structure, andelectrically connected to the first RDL structure through the TIV. Afirst contact area between the encapsulant and the first polymer layerof the first RDL structure is larger than a second contact area betweenthe enecapsulant and a second polymer layer of the second RDL structure.

In accordance with some embodiments of the disclosure, a method ofmanufacturing a package structure includes the following steps. A RDLstructure is formed. the RDL structure comprises a polymer layer and aRDL in the polymer layer. A portion of the polymer layer is removed toform a first recess adjacent to a die attaching region of the RDLstructure in the polymer layer. A die is attached to the die attachingregion of the polymer layer through an adhesive layer. An encapsulant isformed on the RDL structure to encapsulate sidewalls of the die andsidewalls of the TIV. The encapsulant fills into the first recess of thepolymer layer. A conductive terminal is formed to electrically connectedto the die and the RDL structure.

The foregoing outlines features of several embodiments so that thoseskilled in the art may better understand the aspects of the disclosure.Those skilled in the art should appreciate that they may readily use thedisclosure as a basis for designing or modifying other processes andstructures for carrying out the same purposes and/or achieving the sameadvantages of the embodiments introduced herein. Those skilled in theart should also realize that such equivalent constructions do not departfrom the spirit and scope of the disclosure, and that they may makevarious changes, substitutions, and alterations herein without departingfrom the spirit and scope of the disclosure.

What is claimed is:
 1. A package structure, comprising: a die on aredistribution layer (RDL) structure, wherein the RDL structurecomprises a polymer layer and a RDL in the polymer layer; an encapsulanton the RDL structure and laterally aside the die, wherein theencapsulant comprises a body part and an extending part underlying thebody part; and a conductive terminal, electrically connected to the RDLstructure and the die, wherein the body part of the encapsulantencapsulates sidewalls of the die, the extending part of the encapsulantextends into the polymer layer, and a bottom surface of the extendingpart is in contact with the RDL and/or the polymer layer of the RDLstructure.
 2. The package structure of claim 1, wherein the extendingpart of the encapsulant is overlapped with the polymer layer in adirection parallel with a top surface of the die.
 3. The packagestructure of claim 1, wherein the bottom surface of the extending partof the encapsulant is lower than a top surface of the RDL structure, anda sidewall of the extending part of the encapsulant is in contact withthe polymer layer.
 4. The package structure of claim 3, wherein aportion of the bottom surface of the extending part is in contact withthe RDL.
 5. The package structure of claim 1, wherein the polymer layercomprises: a first polymer layer, wherein the RDL is located on thefirst polymer layer; and a second polymer layer on the first polymerlayer and on the RDL, wherein the extending part of the encapsulantextends into the second polymer layer.
 6. The package structure of claim5, wherein the extending part of the encapsulant further extends intothe first polymer layer.
 7. The package structure of claim 1, furthercomprises a through integrated fan out via (TIV) penetrating through theencapsulant and the polymer layer of the RDL structure, and iselectrically connected to the RDL, wherein the extending part is locatedbetween the TIV and the die.
 8. The package structure of claim 1,further comprising an adhesive layer between the die and the RDLstructure, wherein a portion of the adhesive layer extends into thepolymer layer.
 9. The package structure of claim 8, wherein the portionof the adhesive layer is separated from the extending part of theencapsulant by the polymer layer therebetween.
 10. The package structureof claim 8, wherein the portion of the adhesive layer is in contact withthe extending part of the encapsulant.
 11. A package structure,comprising: a die on a first polymer layer of a first RDL structure; aTIV, located on and connected to the first RDL structure, and laterallyaside the die; an encapsulant on the first RDL structure, encapsulatingsidewalls of the die and sidewalls of the TIV; a second RDL structure onthe die, the TIV and the encapsulant; and a conductive terminal,electrically connected to the die through the second RDL structure, andelectrically connected to the first RDL structure through the TIV,wherein a first contact area between the encapsulant and the firstpolymer layer of the first RDL structure is larger than a second contactarea between the encapsulant and a second polymer layer of the secondRDL structure, wherein a bottommost surface of the encapsulant is higherthan a bottommost surface of the first RDL structure and lower than atopmost surface of the first RDL structure.
 12. The package structure ofclaim 11, wherein a portion of the encapsulant has a step profile. 13.The package structure of claim 11, wherein the die is attached to thefirst polymer layer through an adhesive layer; and a contact areabetween the adhesive layer and the first polymer is larger than acontact area between the adhesive layer and the die.
 14. The packagestructure of claim 11, wherein the RDL structure further comprises a RDLin the first polymer layer; the bottommost surface of the encapsulant islower than a top surface of the first polymer layer; and the bottommostsurface of the encapsulant is higher than, coplanar with, or lower thana bottom surface of the TIV.
 15. The package structure of claim 14,further comprises a dummy RDL in the first polymer layer, wherein thedummy RDL is laterally aside and electrically isolated from the RDL, andthe dummy RDL is overlapped with the die.
 16. A method of manufacturinga package structure, comprising: forming a RDL structure comprising apolymer layer and a RDL in the polymer layer; removing a portion of thepolymer layer to form a first recess adjacent to a die attaching regionof the RDL structure in the polymer layer; attaching a die to the dieattaching region of the polymer layer through an adhesive layer; formingan encapsulant on the RDL structure to encapsulate sidewalls of the die,wherein the encapsulant fills into the first recess of the polymerlayer, the encapsulant comprises a body part and an extending partunderlying the body part, the body part of the encapsulant encapsulatessidewalls of the die, the extending part of the encapsulant extends intothe polymer layer, and a bottom surface of the extending part is incontact with the RDL and/or the polymer layer of the RDL structure; andforming a conductive terminal electrically connected to the die and theRDL structure.
 17. The method of claim 16, further comprising forming aTIV penetrating through the polymer layer to electrically connect to theRDL before attaching the die, and the encapsulant is further formed toencapsulant sidewalls of the TIV, wherein the first recess is formedbetween the TIV and the die.
 18. The method of claim 16, wherein theremoving the portion of the polymer layer further comprising forming asecond recess in the polymer layer.
 19. The method of claim 18, whereinthe adhesive layer fills into the second recess of the polymer layer.20. The method of claim 16, further comprising the adhesive layerfilling into the first recess.